Based on the prevalence rates published by Public Health England in 2016, and population data from the Office for National Statistics (2019), the estimated prevalence of learning disabilities in children in the UK is 2.5% and 2.16% in adults.1
Adults with a learning disability (LD) are 10 times more likely to have an eye or vision problem.2 For children with LD, this increases to a staggering 28 times. By contrast, sight problems are comparatively rare in the general paediatric population.3
While children in full-time education in England are entitled to regular NHS sight tests, there is strong evidence that children and young people with learning disabilities have problems accessing community eye care services.3-5 In part, this is linked with a perceived lack of practitioner confidence and limited access to ‘specialist’ skills and equipment. The emphasis here is on the word ‘perceived’.
Underlying any clinical assessment of an LD patient is the importance of engagement and reassurance, especially on initial meeting and during key tests. Visual and musical stimuli are essential for optimal engagement.6
One new and promising way of helping to maintain attention during refraction is the Visual Fixation System developed by optometrist Simon Berry; look out for a review in the coming weeks. There are also a number of apps available, many free, that can easily be run on a tablet or smartphone and can be very helpful in maintaining the interest and cooperation of someone with a severe learning disability, and in some cases may offer clues to the level of their vision. Here are a few used in our clinic.
Fluidity (free, iOS 12 and earlier)
This free to download app has been a stalwart of LD assessment for a while. Unfortunately, at the time of writing, it is still only available on older iOS versions so will not run on newer tablets and smartphones until updated by the designers; let us hope this happens soon.
In essence, the app presents a brightly coloured display of shades and dots in a fluid pattern that can be moved about with the touch of a finger (figure 1). The viscosity, colours, speed and fade of movements and ‘sparkliness’ can all be pre-set. The reason this app has proved so effective is that most LD patients also respond well to the very ‘new age’ musical tone that plays with each sweep of the display; think Rainbow Dome Musick by Steve Hillage.
Baby Bubbles Babble (free, iOS and Android)
This app has proved popular for young children and adults alike as, essentially, it gives the same pleasure as popping bubble wrap. Best run on a tablet, this simple app displays rising bubbles of different size, colour and speed of movement which, when touched, burst with a pleasing ‘pop’ (figure 2). The background music is Brahms’ lullaby on piano, which is less annoying than the occasional and, in my view unwanted, baby gurgles and coos which also accompany the bursting. As well as helping with attention, the task also offers some indication of visual tracking and hand-eye coordination and location.
Other bubble bursting apps are available, but tend to have ads and cost money.
Figure 2: Baby Bubbles App
Sensory Plazma (free, iOS and Android)
This app is presumably named because of its display resembling those 1960s plasma lamps beloved of hippies. Not so good on the sound front, but the display shows moving blobs of colour in both 2D and 3D format (figure 3). The size, speed, number and type of blob can all be changed with onscreen buttons. Also, the blobs can be moved about on-screen by touching.
The screen can be linked to a Bluetooth keyboard which allows easier display change by the clinician. The app maintains patient attention and also helps assess tracking and hand-eye coordination.
Figure 3: Four different Sensory Plazma displays
Sensory Aqua (89p, or part of £5.10 bundle. iOS and Android)
The Sensory Aqua app can be downloaded on its own or as part of a bundle called the Sensory Room App Pack 1. The Aqua app is most useful for LD assessments and, like the Plazma app, allows a good degree of control over the size, speed and colour of the blobs, again with button control (figure 4). These do make a noise when touched, some of which are a little too jarring, so I silence them.
Figure 4: Six displays on the Sensory Aqua app
Eda Play Toby (free, iOS and Android)
This app has been designed specifically to help with the training and development of visual and fine motor skills for children with multiple sensory impairments (figure 5). The app runs through four separate stages. In the first, the child can simply watch a range of images with accompanying noises and is useful for maintaining attention. The remaining three stages offer interaction and allow the child to trigger a noise or a hidden image by touching the screen at the right place. These obviously are useful for assessment of visuomotor coordination.
Figure 5: Differing displays on the Eda Play Toby app, offering audio and visual stimuli and simple location and recognition tasks
OKN Drum (£3.49, iOS and Android)
For the very young and those with severe learning impairment, sometimes an optokinetic nystagmus reflex is all you can achieve reliably as an indicator of visual functioning. For years, this meant lugging around a cumbersome Catford drum (figure 6a), but now an excellent app performs the same function on your tablet (figure 6b). The speed of line movement vertically is controlled by tapping the screen (seven speeds available in both up and down motion) and it is easy to elicit a vertical nystagmus movement when held in front of any patient, so proving the presence of visual function. The size of the lines can be set on-screen too (figure 6c).
Figure 6: (left to rigt) (a) Catford drum, (b) OKN Drum app, (c) Changing size of display
YouTube and more
Finally, be innovative; it is both fun and fulfilling. I have had some excellent results by simply playing a Peppa Pig video or, most recently, a Whitney Houston video. The LD patient had great fun trying to touch her nose as she danced (‘with somebody’), and this not only maintained his attention but also helped decide on his level of vision. And, of course, there is no reason not to play good old Steve Hillage (or your own preferred choice) in the background for any display.
Acknowledgements
The author would like to thank Dr Louise Gow, RNIB specialist lead for eye health, for her assistance with this article
References
- Rughani S, Donaldson L. Eye care for children with learning disabilities – 1. Epidemiology and the case for a national programme of eye care. Optician, 12.06.2020, pp17-23
- Emerson E, Robertson J. The estimated prevalence of visual impairment among people with learning disabilities in the UK. RNIB SeeAbility [Internet]. 2011;35. Available from: http://www.rnib.org.uk/aboutus/Research/reports/20...
- Das M, Spowart K, Crossley S, Dutton GN. Evidence that children with special needs all require visual assessment. Archives of Disease in Childhood, 2010;95(11):888–92
- Hall DMB, Elliman D. Health for all children (online). 2006. Available from: http://ovidsp.ovid.com/ovidweb.cgi?T=JS&PAGE=refer...
- Pilling RF, Outhwaite L. Are all children with visual impairment known to the eye clinic? British Journal of Ophthalmology, 2017, Apr;101(4):472–4
- Rughani S, Donaldson L. Eye care for children with learning disabilities – 2. Assessment of vision and visual needs. OPTICIAN 21.08.2020, pp22-2